"The lawsuit is without merit," he said. "We will contest it vigorously."

Beef Products spokesmen say that after the media reports ran, the company was forced to close three of its four plants in the United States and lay off 650 employees.

Lean beef trimmings is a disinfected, heavily processed ground beef that is used as an additive in ground beef products. In 2004, the Food and Drug Administration approved it for human consumption, provided that it constitutes no more than 15 percent of a food product.